The present invention relates to waveform display instruments, and more particularly to a cursor interface for waveform displays which allows an operator to adjust the relative positions of a displayed waveform and measurement cursors in a fast, intuitive manner.
In traditional cursor control systems each cursor has its own control knob and the waveform display has a gain and position adjustment. To make measurements between two points on the waveform the gain and position of the waveform have to be adjusted so that both points on the waveform are displayed. Then the cursors are separately adjusted to overlie the respective points and the resulting measurement is read from the graticule scale on the display. For small intervals, such as the width of a horizontal sync pulse in a television video signal, this technique provides fairly accurate results. However for large measurement intervals, like the interval between succeeding horizontal sync pulses, the measurement accuracy is considerably less.
Therefore, what is desired is a cursor interface with the waveform display which provides the ability for accurate measurements between cursors over all intervals.